1. Field of Use
This disclosure is directed to an image-forming apparatus and an intermediate transfer member.
2. Background
Image-forming apparatuses in which a color or black and white image is formed by using an intermediate transfer member to electrostatically transfer toner are well known. When an image is formed on a sheet of paper in a color image-forming apparatus using such an intermediate transfer member, four color images in yellow, magenta, cyan and black respectively, are generally first transferred sequentially from an image carrier such as a photoreceptor and superimposed on the intermediate transfer member (the primary transfer). This full color image is then transferred to a sheet of paper in a single step (the secondary transfer). In a black and white image-forming apparatus, a black image is transferred from the photoreceptor, superimposed on an intermediate transfer member, and then transferred to a sheet of paper.
Conductive carbon black usually has a very narrow percolation threshold range. The common logarithm of an intermediate transfer member surface conductivity (Ω/□) is in the range of 8 to 13. Carbon black is a filler in films, both in transfer members and fusers, so its dispersion uniformity and interaction with polymeric resins have significant impact on the performance of these films. In coating solutions, conductive carbon black is dispersed in polymeric binder(s) with organic solvent(s). Due to the high solution viscosity required for coating these belts, the in-situ dispersion of carbon black in a polymeric solution is very difficult. Common problems in current coating processes in intermediate transfer members include non-uniform carbon black dispersion distributions, coating defects and variable conductivity.
There is a need to develop new intermediate transfer member materials processes that are repeatable and provide an acceptable transfer member having suitable properties.